genotypic and allelic prevalence of the tgf- β1 +869 c/t snp and their relationship to seminogram in infertile males

Background: the influence of cytokine in the reproductive system is becoming increasingly important. the polymorphisms of the transforming growth factor-β1 (tgf-β1) gene are involved in male infertility. this study aimed to demonstrate the association between tgf-β1 and infertility and to investigate its impact on semen quality. methods: in this case-control study, serum tgf-β1 concentration was measured in 144 patients diagnosed with infertility and 40 fertile males by enzyme-linked immunosorbent assay (elisa). the tetra-amplification refractory mutation system-pcr (t-arms-pcr) analysis was performed to detect the genotyping of the tgf-β1 (+869 c/t) (rs1800470) snps gene.results: serum concentration of tgf-β1 was less in infertile males compared to fertile ones. the detected and more effective genotypes and alleles of tgf-β1 gene polymorphic on male infertility were, in normozoospermic group, ct genotype, probability (p)= 0.45, relative risk (rr)= 1.56, confidence intervals (ci): 0.58–4.22, and t allele (p= 0.46, rr= 1.32, ci: 0.65—2.69), in oligozoospermic and azoospermic groups, cc genotype (p= 0.32, rr= 1.58, ci: 0.73–3.41), (p= 0.013, rr= 3.50, ci: 1.40–8.73), and allele c (p= 0.44, rr= 1.32, ci: 0.73–2.38), (p= 0.06, rr= 2.14, ci: 1.02–4.50), respectively. the recessive model (tt+ct) showed increased risk among normozoospermic group (p=0.44, rr=1.67, ci:0.60-4.62). the serum concentration of tgf-β1 with ct and tt genotypes was less than that of cc genotype. tgf-β1 c/t genotype correlated with low sperm number, high immotile sperm, and high abnormal sperm morphology.conclusions: our study revealed that the tgf-β1(rs1800470) gene polymorphisms are associated negatively with semen quality.